Non-ionic gas separation methods although widely used in the chemical industry are sometimes inefficient, especially if the components to be separated are chemically closely related, or are isotopic elements or compounds, or in view of very high temperatures or pressures used the separation is incomplete. The gaseous diffusion method, for example, requires a very high initial investment, needs many sequential stages for a moderate enrichment of a desired compound, and requires for its operation enormous amounts of power.
The centrifugal and nozzle processes, while offering higher separation factors, are subject to mechanical breakdowns and disruptions, and due to large power consumption are also quite uneconomical.
In conventional electromagnetic mass separators only the ions of a gas mixture are accelerated by an electric field, deflected by a powerful magnetic field according to the ion mass value, and fed into separate exit ports for collection. This method of mass separation consumes much power, and yet produces only very small flow rates due to space charge effects. For example, the Calutron mass separator consumes over 150,000 kilowatt-hours for processing just one kilogram of ionized matter. Electromagnetic mass separation has therefore been restricted to small-scale extraction of rare elements, and of stable or radio-active isotopes needed for medical or scientific purposes.